Cé acu Is Categorach agus Cineálacha na nRialaithe agus na dIaigh FACTS?
De réir an t-seónra comhcheangailte leis an gcóras fhuinnimh, rachadh an Cóntrólaí FACTS ina chloch:
Cóntrólaí Cothromán
Cóntrólaí Iompúil
Cóntrólaí Cothromán-Cothromán Comhcheangailte
Cóntrólaí Iompúil-Cothromán Comhcheangailte
Cóntrólaí Cothromán-Comhcheangailte
Intreoirí cothromán voltas i gcothromán leis an ngnéas domhain, go minic trí úsáid eileamhan impídaithe capaitíochta nó induicithe. Is é an príomhfheidhm a bhfuil acu ná aon phuiss reachtúil athraitheach a thabhairt ar fáil agus a ghlacadh mar is gá.
Nuair atá líne trasnála lánlódaithe, sásítear an méadú forbartha puissa reachtúil trí eileamaí capaitíocha a chur i bhfeidhm sa chóntrólaí cothromán. Ar an mbonn cosúil, faoi mhodh lódha íseal—nuair d'fheabhsóidh an t-iarratas ar phuiss reachtúil agus d'éireoidh sé go mbeidh an voltas deiridh os cionn an voltsa tosaigh—úsáidtear eileamaí induicithe chun an puiss reachtúil breise a ghlanadh, ag stiúradh an chóras.
Sa chuid is mó de na feidhmeanna, cuirtear cainteoirí i gcomhcheangal lárnach le haghaidh an líní trasnála chun an iarratas ar phuiss reachtúil a shásamh. Cainteoirí tréitheacha do scéimeanna seo inchlúdálacha Cóntrólaí Capaitíocha Sraithe Sraithe (TCSC) agus Cómpensatóirí Sraithe Státacha Sraithe (SSSC). Tá an struchtúr bunúsach cóntrólaí cothromán-ghorthaíthe léirithe sa dhuais thíos.
Cóntrólaí Iompúil-Comhcheangailte
Intreoirí iompúil cóntrólaí iompúil an córas fuinnimh ag a bpunt cothache, ag úsáid impídaithe athraitheacha cosúil le cainteoirí agus induicithe—cothroimeach i gprionsabal le cóntrólaí cothromán ach éagsúil i gcomhcheangal.
Compensáid Capaitíochta Iompúil
Nuair a chuirtear cainteoir i gcomhcheangal iompúil leis an gcóras fuinnimh, úsáidtear an modh sin chun compensáid capaitíochta iompúil. Oibríonn línte trasnála le lódha induictí go minic ag factor púirt lag. Díríonn cainteoirí iompúil orthu trí thomhais a dhíol cad a leanann an tsruth foinsí, ag oibriú in aghaidh an lódha lag agus ag feabhsú ar an factor púirt iomlán.
Compensáid Induicithe Iompúil
Nuair a chuirtear induice i gcomhcheangal iompúil, úsáidtear an modh sin chun compensáid induicithe iompúil. Níl an modh seo chomh coitianta agus an modh capaitíochta i mpáirceáin trasnála, ach tá sé riachtanach do línte an-fada: faoi staid neamhlódha, lódha íseal, nó lódha díchomhcheangailte, d'fheabhsóidh an effect Ferranti an voltsa deiridh os cionn an voltsa tosaigh. Ghlacfaidh compensátoirí induicithe iompúla (mar shampla, reactors) an puiss reachtúil breise chun an meastú voltas a laghdú.
I measc córais cóntrólaí iompúil-ghorthaíthe, tá Compensatóirí VAR Státacha (SVC) agus Compensatóirí Sraithe Státacha (STATCOM).
Cóntrólaí Cothromán-Cothromán Comhcheangailte
I gcórais trasnála il-líní, úsáideann cóntrólaí cothromán-cothromán comhcheangailte sraith de chóntrólaí cothromán neamhspleách ag obair in ollmhuintearas. Seo a chur in áit an córas seo an tacaíocht reachtúil sraithe aonair don gach líne, ag dearbhú tacaíocht sonraithe do gach ciorcal.
Is féidir leis na córais seo freisin an t-iontráil púirt fíorach idir línte a spreagadh trí nasc púirt shonraithe. Mar alt, d'fhéadfadh siad a bheith ina dhuine aonréimeach cóntrólaí ina dtugtar comhcheangal ar teiripe DC na ndeachóir—seo a chur in áit an córas seo an t-iontráil púirt fíorach go díreach chuig na línte trasnála. Is é an Interlink Power Flow Controller (IPFC) sampla iontaofa den chóras seo.
Cóntrólaí Iompúil-Cothromán Comhcheangailte
Integrateann an cóntrólaí seo dhá chomponent gníomhach: cóntrólaí iompúil a intreoirí voltas i gcomhcheangal leis an gcóras, agus cóntrólaí cothromán a intreoirí sruth i gcothromán leis an líne. Is minic a oibríonn na dha chomponent seo in ollmhuintearas chun an t-eifeacht iomlán a bhaint amach. Is é an Unified Power Flow Controller (UPFC) sampla iontaofa den chóras seo.
Cineál Eileamh FACTS
Tá roinnt eileamh FACTS forbairt chun riachtanais feidhmiúla éagsúla a shásamh. Anseo thíos léargas ar na cóntrólaí FACTS is coitianta, catagóilte de réir a cineál gníomha:
Compensatóirí Sraithe:
Compensatóirí Iompúla:
Compensatóirí Sraithe-Sraithe:
Compensatóirí Sraithe-Iompúla:
Breathnóidh muid ar gach compensatóir go gairid:
Thyristor Controlled Series Capacitor (TCSC)
Intreoirí TCSC reactance capaitíochta i gcothromán leis an gcóras fuinnimh. Tá a struchtúr bunúsach bunaithe ar banc cainteoir (comhdhéanta as roinnt cainteoirí i gcothromán-sraithe) a chuirtear i gcomhcheangal le reactor Thyristor-ghníomhach. Seo a chur in áit an córas seo an seiceáil capacitance sraithe a athrú go sothuile.
Seiceálann Thyristors an impíd an chórais trí rialú an uillin a lasadh, a athraíonn an impíd circuit iomlán. Tá diagram bloc shimplí den TCSC léirithe sa dhuais thíos.
Thyristor Controlled Series Reactor (TCSR)
Tá TCSR ina chóntrólaí sraithe a thugann reactance induicthe a athraíonn go sothuile. Tá a dhréacht bunaithe ar an TCSC, leis an difríocht príomha ná go bhforbraítear an cainteoir le reactor.
Staidéar an reactor nuair a shroicheann an uillin a lasadh 180°, agus thosaíonn sé ag condae nuair a bhíonn an uillin a lasadh níos lú ná 180°. Tá diagram bunúsach den Thyristor Controlled Series Reactor (TCSR) léirithe sa dhuais thíos.
Thyristor Switched Series Capacitor (TSSC)
TSSC is a series compensation technique similar in principle to TCSR but with a key operational difference: while TCSR achieves power control by adjusting thyristor firing angles (enabling stepwise regulation), TSSC thyristors operate in a simple "on/off" mode with no firing angle adjustment. This means the capacitor is either fully connected to or completely disconnected from the line.
This simplified operation reduces the complexity and cost of both the thyristors and the overall controller. The basic diagram of TSSC is identical to that of TCSC.
Static Synchronous Series Compensator (SSSC)
SSSC is a series compensation device used in transmission systems to regulate power flow by controlling the equivalent impedance of the line. Its output voltage is fully controllable and independent of the line current—by adjusting this output voltage, the line’s effective impedance can be precisely modulated.
Functionally, SSSC acts like a static synchronous generator connected in series with the transmission line. Its core purpose is to adjust the voltage drop across the line, thereby controlling power flow. SSSC injects a voltage that is in quadrature (90° phase shift) with the line current: if the injected voltage leads the current, it provides capacitive compensation; if it lags the current, it provides inductive compensation.A basic diagram of the Static Synchronous Series Compensator is shown in the figure below.
Static VAR Compensator (SVC)
A Static VAR Compensator (SVC) consists of a fixed capacitor bank connected in parallel with a thyristor-controlled inductor. The thyristor’s firing angle regulates the reactor’s operation, directly controlling the voltage across the inductor—and thus the amount of power it draws.
This configuration allows SVC to dynamically adjust reactive power output, stabilizing voltage and improving power factor in the transmission system. A basic diagram of the Static VAR Compensator is shown in the figure below.
Static VAR Compensator (SVC) Applications
SVCs are versatile devices used to enhance power system performance, with key functions including:
They are also widely adopted in industrial settings for reactive power management and power quality improvement. Below is an overview of the most common SVC configurations:
Thyristor Controlled Reactor (TCR)
A TCR consists of a reactor connected in series with a thyristor valve—specifically, two thyristors connected in anti-parallel. These thyristors conduct alternately during each half-cycle of the AC power supply, with a control circuit delivering firing pulses to the thyristors every half-cycle.
The thyristor firing angle determines the amount of lagging reactive power supplied to the system. TCRs are commonly deployed in EHV (Extra High Voltage) transmission lines, where they provide reactive power compensation during light-load or no-load conditions. A basic diagram of a Thyristor Controlled Reactor is shown in the figure below.
Thyristor Switched Capacitor (TSC)
Under heavy load conditions, reactive power demand surges—and Thyristor Switched Capacitors (TSCs) are designed to meet this increased demand. They are commonly deployed in EHV transmission lines during periods of high load.
TSC shares a similar structural principle with TCR, but with a key component swap: the reactor in TCR is replaced by a capacitor. Like TCR, TSC regulates the amount of reactive power supplied to the transmission line by adjusting the thyristor firing angle.A basic diagram of the Thyristor Switched Capacitor (TSC) is shown in the figure below.
Thyristor Switched Reactor (TSR)
TSR is structurally similar to the Thyristor Controlled Reactor (TCR) but differs in operation: while TCR adjusts current by controlling thyristor firing angles (enabling phase control), TSR thyristors operate in a binary "on/off" mode with no phase control. This means the reactor is either fully connected to the circuit or completely disconnected.The absence of firing angle regulation simplifies the design, reducing thyristor costs and minimizing switching losses. The basic diagram of a TSR is identical to that of a TCR.
Static Synchronous Compensator (STATCOM)
STATCOM is a power electronics-based voltage source converter (VSC) that regulates transmission system performance by supplying or absorbing reactive power—and can also provide active power support when needed. It is particularly effective in transmission lines with poor power factor and voltage regulation, making it a widely used device for enhancing voltage stability in power systems.
STATCOM operates using a charged capacitor as its DC input source, which is converted into three-phase AC voltage via a voltage-controlled inverter. The inverter output is synchronized with the AC power system, and the device is connected in shunt with the transmission line through a coupling transformer. By adjusting the inverter’s output, the reactive (and active) power supplied by STATCOM can be precisely controlled. A basic diagram of STATCOM is shown in the figure below.
Interline Power Flow Controller (IPFC)
IPFC is a compensation technique designed for multi-line transmission systems, featuring multiple converters linked via a common DC bus—each converter connects to a separate transmission line.
A key capability of these converters is real power transfer, enabling both real and reactive power to be balanced across interconnected lines. This coordinated control enhances overall system efficiency and stability in multi-line networks.A basic diagram of the IPFC is shown in the figure below.
Unified Power Flow Controller (UPFC)
UPFC integrates a STATCOM (Static Synchronous Compensator) and an SSSC (Static Synchronous Series Compensator) via a shared DC voltage link, combining their functionalities into a single system. It utilizes a pair of three-phase controllable bridges to generate current, which is injected into the transmission line through a coupling transformer.
UPFC excels in enhancing multiple aspects of power system performance, including voltage stability, power angle stability, and system damping. It can precisely control both active (real) and reactive power flow in transmission lines. However, it operates optimally only under balanced sine wave conditions and may not function effectively during abnormal system states. Additionally, UPFC helps suppress power system oscillations and improves transient stability.A basic diagram of the Unified Power Flow Controller (UPFC) is shown in the figure below.
